There are. two general types of 'rubber hydrochloride nlm 'o n lthe market. One type is the of the plasticized and unplasticized films, two

types of bags have been designed. One type of .bag is theduple'x or double-wall bag. Thisv comprises a bag of Aunplasticized nlm on'the inside and a separate bag of plasticized nlm on'the outside. The'two bags are generally united only at the bottom. The plasticized nlfn of which the outside bag is made givesthe product the dur-,-

ability and strength characteristic ofthe plas-.9.

ticlzed nlm. The unplasticized bag on the inside prevents contamination f the contents-byV the plastic'zed nlm. There have been vcertain objections to a bag of this type. One objection, A'

bag.

To overcome this objection, there has been: de-

the outer ply is plasticized. gives the strength of the plasticized nlm on the outside, and the freedom from contamination due to the presence of the unplasticized nlm on the inside.`

To give the increase in visibility which has preunplasticized nlm', and the l other type is the 5 plasticized nlm. The usual plasticizers are butyl viously been obtained by uniting the two plies stearate and dibutyl phthalate. These may be of nlm, the two sheets of nlm comprising each used alone or in admixture. A small amount of wall of the bag are united, but at the folds the wax may be added. l two plies are not united. By not laminating at `It isy recognized that the unplasticized nlm does 10 thefolds, the danger 0f leaks developing at the not have the strength and durability of the plas- Vcreases is reduced or eliminated. 1 ticized nlm. The plasticized nlm is vtherefore One type 0f bas hal/1118121115 Structure is Shown preferred in many cases, but in certain instances, in the accompanying drawing. The inner ply l asin the packaging4 of foodstuffs, the plasticizer S unplasticized film, and the Outer Ply 2 1S Qf is at times found to be objectionable because the l5 plasticized nlm. The two plies are united l plasticizer brings about contamination of the y throughout the'enter DOIOn 0f the center walls food. This is particularly noticeable in deliv las indicated by the heat-'seals 3 and 4. They are cately flavored foodstuffs and foodstuffs which not united at the side creases 5 and 6. The long readily absorb odors. v f side seams I and 8 are formed by heat-sealing. In order to. combine in bags the advantages 20 The bag may be formed by inserting a long tube of unplasticized nlm inside a-long tube of the plasticized nlm, uniting opposite walls with heat and pressurevto form the sides of the bags and cutting them to length. The bottoms of the bags may be formed by heat-sealing one end ofV each of the .lengths together, or folding and sealing,

as desired.v

suitable manner. Y

'.'Iclaim:HV

1. A bag formed of plasticized rubber hydro-` chloride nlm and unplasticized rubber hydrochloride nlm coalesced together at the bottom in anat seam, all seams of the `bag being formed by `coalescence of the nlm material, the plasticized nlm being outside the unplasticized nlm and the veloped a bag made of laminated nlm', the inner p1y or which is unmasncized nlm 'and the outer ply of which is plasticized nlm. Such. a bag has the high visibility of a single wall bag.' vThere have been objections to this type of bag, particularly because of the -levelopment of 'leaks at Y Apparently the nlm cracks or lis weakened byfolding this laminated sheet. Such Icreases are present in a bag of the envelope type' i the creases.

and a bag with plicated sides and,"inV fact, any type of bas.

'.two nlms being coalesced together over most of 1 mgjthe .area of each side of the bag to increase'the y --Kanother at the twoedges of the bag where the nlm' is creased. y

visibility of the contents, but being freeirom one I 2. vAbag formed of two nlms of heat-scalable,

transparent nlm united `at the bottom ina nat- 'seaan,` all .seams lof the bag being formed by `coalescence of the nlm, each-of the two nlms being calescedv to the .otherv on both sides of the basto increase'the visibility ofthe contents but being free from one' another at the twoedges of thel bag where the nlms are folded.